![]() ![]() So, make is as simple and stupid as possible and concentrate on the pseudo random number generator. Ive been rehashing some existing libraries I found on some obscure forums to measure a frequency on digital pin 5, using the ATmega328P/ATmega2560 Timer/Counter modules and an interrupt based approach in order to be able to measure frequencies up to 4MHz (-ish). when the TOV1 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. The two 8-bit timer-counter counts up to 255 and one 16-bit timer counts up to 65535. This means we have total 3 timers in our chip. The corresponding interrupt (at vector 010) is executed if an overflow in Timer/Counter1 occurs, i.e. Here in this case, we will use AVR Atmega32A microcontroller which has two 8-bit and one 16-bit timer. In all cases, the algorithm that you will use to generate the pseudo random numbers is much more important than the seed generation approach. When the TOIE1 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 Overflow interrupt is enabled. This way, the human provided switch ON will provide random moment event. of the result that is generated by execution of certain instructions. This way you will get better randomization, because the RTC runs even if the whole devide is switched off. SBUF (Serial Data Buffer) TL0/TH0 (Timer 0 Low/High) TL1/TH1 (Timer 1 Low/High). If your device supports real time clock, use it. This way, you can use for example some of the timers, configured to the fastest possible frequency, or even a simple software counter incremented on every main program loop (of course if the program is fast enough). Atmega328 has one 16 bit timer, which is more powerful comparing to 8-bit timers. Several kilohertz is a acceptable frequency. This way, you can use for example some of the timers, configured to the fastest possible frequency, or even a simple software counter incremented on every main program loop (of course if the program is fast enough). ![]() The only requirement to it is to run much more faster then the human reaction time. Simple delays can be produced using the timer/counter1 by writing the required delay values into the respective registers. The counter is not actually so important. The Timer/Counter1 module in ATmega328P The 16-bit Timer/Counter unit allows accurate program execution timing (event management), wave generation, and signal timing measurement. In the computers, the human randomizes the moment of the program start. Without human interaction, it is not possible to get random number seed using timer or counter. In order to do it, you need a timer/counter that counts fast and continuously and human that actually performs as a random event generator. March 29th, 2018 - Introduction to the ATmega16 Atmel 1 Introduction to the Atmel ATmega 16 Microcontroller Learning Objectives At the end of this lab. You can use it only as a source for the pseudo random algorithm seed number. May 1st, 2018 - ll the Atmel microcontrollers have Timers as an inbuilt Atmega series of microcontrollers are available in several frequencies AVR. ![]() Its advantage is that the input clock and operation of the timer is independent of the program. I see, you know it, but to emphasize once again, you can't use any timer/counter value as random number generator. In principle, a timer is a simple counter. ![]()
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